.top{
	height: 50px;
	width: 750px;
	background-color: cornflowerblue;
	margin: 0 auto;
	margin-top: 50px;
	text-align: center;
	line-height: 50px;
}
.quan{
	height: 550px;
	width: 750px;
	background-color: lightcyan;
	margin: 0 auto;
	
}
.a{
	height: 50px;
	width: 800px;
	
}
